Effect of light polarization on holographic recording in glassy azocompounds and chalcogenides

Abstract

Abstract:Light polarization effects on a holographic grating recording in a glassy chalcogenide a-As 40 S 15 Se 45 film has been experimentally studied and compared with previously studied glassy molecular azobenzene film 8a at 633, using − − , CE-1 and CE-2 circular-elliptic recording-beam polarizations (differing by light electric field rotation directions). The azocompound exhibited much higher self-diffraction efficiency (SDE) and diffraction efficiency, whereas chalcogenide was more sensitive. Their recording efficiency polarization dependences also were different. SDE up to 45% was achieved in 8a with − and up to 2.6% in a-As 40 S 15 Se 45 with CE-2 polarized recording beams. The polarization changes in the diffraction process were studied as well in these and other materials (11, 16, 19 and a-As 2 S 3 film, LiTaO 3 :Fe crystal). It was found that light polarization changes in the process of diffraction from gratings recorded vectorially by − polarizations depended on chemical composition, wavelength, and exposure time. Vector gratings with SDE up to 25% were recorded in 8a, rotating a linear polarization by 90°. No light polarization changes were found in azobenzene 19 and chalcogenide films and in LiTaO 3 :Fe crystal, thus showing a vector recording of scalar holograms. The recording mechanisms in azocompounds and chalcogenides are discussed and compared. 42.25.Ja, 42.25.Gy, 68.35.bj, 68.35.bm PACS (2008):

Photoinduced mass transport in low molecular organic glasses and its practical application in holography

“…Despite of the large amount of the studied materials -organic [11][12][13][14][15][16][17][18], inorganic [19][20][21], composites [22][23][24] and polymers of different chemical compositions [25][26][27][28][29], the direct relief formation phenomenon used in practice is limited. One of the most critical issues is the amount of energy required for the formation of the SRG.…”

“…Secondly, there are different types of polymers in which the diazo group is chemically incorporated into the polymer chain [27,32], or attached as side groups [25,26,29,33,34]. And thirdly, there are low molecular weight organic glasses (LMOG) capable of forming an optically uniform film of thickness up to several microns [11][12][13][14][43][44][45].…”